Former Biden White House national security adviser Jake Sullivan said the meeting between President Donald Trump and Ukrainian President Volodymyr Zelenskyy in Rome Saturday gave him "the first sliver of hope" he said he has had in a while as it relates to the current administration's approach to the war in Ukraine.

"[The meeting] gives me the first sliver of hope I've had in a while because what I've seen to date is President Trump giving Vladimir Putin U.S. recognition of Crimea, which Russia illegally occupied and annexed. ... He's given Putin a promise that Ukraine will not be part of NATO, and he has given Putin a promise that he can keep all the territory that he has illegally invaded and seized," Sullivan told "This Week" co-anchor Martha Raddatz in an interview that aired Sunday.

He continued, "What is Putin giving him? So far nothing. But today having Zelenskyy come out and say he thought it was a good meeting, makes me think, 'OK, maybe President Trump is seeing that Putin is leading him down the garden path.' And in fact, President Trump said publicly that that might be the case."

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